ideas for wall pot please

I found a pile of teracotta pots behind an overgrown lilac - two of them are wall hanging pots, about 1.5L, which I've now hung up against the west-facing side of the house, on the wall screws which I think were originally intended for them (pots were probably taken down by previous owner as too high maintenance - the garden is well planned and planted but recently pretty neglected and I'm discovering all sorts of gems).

I'd like to have something evergreen and perennial in the wall pots. They are quite high on the wall so something trailing would be nice. Not overly worried about whether they flower - primarily after some greenery all year but flowers would be an added bonus. I'm aware that wall mounted terracotta will dry out easily, and happy to look after them i.e. gel in compost, regular watering/feeding etc if necessary.

So, any suggestions on something small ebough to live in a 1.5L container, trailing, evergreen perennial?

There is a slightly weird but lovely succulent which I think, and am quite prepared to be corrected if wrong, Mexican donkeys tail. It grows with no attendtion whatsover, with little white/silver tear drop shaped 'leaves' along the stems which elongate over time. I've never seen it flower, though it has lived here for a goodly nuber of years. Each leaf will produce a new plant given a chance. Should look good in a wall pot - mine is busy taking over a windowsill.